Conventional fire alarm systems providing audible alarms by means of bells, buzzers, and sirens are generally separate and distinct systems apart from any music or paging system which otherwise may also be provided in the building or area desired to be protected. Systems which conventionally utilize existing music or paging systems deliver the alarm by substituting through switches and relays an alarm signal for the normal audio input of such systems. Typically there is no provision in such systems for continuously monitoring the integrity of the audio system or the fire alarm system.